Protective sleeve



FIG. 1 is a right elevation view of a protective sleeve showing my new design;

FIG. 2 is a left elevation view thereof;

FIG. 3 is a front elevation view thereof;

FIG. 4 is a rear elevation view thereof;

FIG. 5 is a top plan view thereof; and,

FIG. 6 is a bottom plan view thereof.

The broken lines in FIG. 1 depict environmental subject matter only and form no part of the claimed design. 

The ornamental design for a protective sleeve, as shown and described. 